-er -ol bbb bbe bbi bbk bbl bbo bbr bbs bbt be- beb bee bei bek bel beo ber bes bet bi- bib bie bii bik bil bio bir bis bit bkb bke bkk bkl bko bkr bks bkt blb ble bli blk bll blo blr bls blt bob boe boi bok bol boo bor bos bot brb bre bri brk brl bro brr brs brt bsb bse bsi bsk bsl bso bsr bss bst btb bte bti btk btl bto btr bts btt ebb ebe ebi ebk ebl ebo ebr ebs ebt eeb eee eek eel eeo eer ees eet eib eie eii eik eil eio eir eis eit ekb eke eki ekl eko ekr eks ekt elb ele eli elk ell elo elr els elt eo- eob eoe eoi eok eol eoo eor eos eot erb ere eri erk erl ero err ers ert es- esb ese esi esk esl eso esr ess est etb ete eti etk etl eto etr ets ett ibb ibe ibi ibk ibl ibo ibr ibs ibt ie- iee iei iek iel ier ies iet iib iie iii iil iio iir iis iit ikb ike iki ikk ikl iko ikr iks ikt il- ilb ile ili ilk ill ilo ilr ils ilt io- iob ioe ioi iol ioo ior ios iot ir- irb ire iri irk irl iro irr irs irt is- isb ise isi isk isl iso isr iss ist itb ite iti itk itl ito its itt k-t kbb kbe kbi kbk kbl kbo kbr kbs ke- keb kee kei kek kel keo ker kes ket kib kie kii kik kil kio kir kis kit kkb kke kki kkk kkl kkr kks kkt kl- klb kli klo klr kls klt kob koe koi kok kol koo kor kos kot kri krk krl kro krr krs krt ksb kse ksi ksk ksl kso ksr kss kst ktb kte ktk ktl kto ktr kts ktt lbb lbe lbi lbk lbl lbo lbr lbs lbt leb lee lei lek lel leo ler les let lib lie lii lik lil lio lir lis lit lkb lkl lkr lks lkt llb lle lli llk lll llo llr lls llt lob loe loi lok lol loo lor los lot lrb lri lrk lro lrr lrs lrt lsb lse lsi lsk lsl lso lsr lss lst ltb lte lti ltk ltl lto ltr lts ltt o-i ob- obb obe obi obk obl obo obr obs obt oeb oee oei oel oeo oer oes oet oib oie oii oik oil oio oir ois oit okb oke oki okk okl oko okr oks olb ole oli olk oll olo ols olt oo- oob ooi ook ool ooo oor oos oot or- orb ore ori ork orl oro orr ors ort os- osb ose osi osk osl oso osr oss ost ot- otb ote oti otk otl oto otr ots ott rbb rbe rbi rbk rbl rbo rbr rbs rbt re- reb ree rei rek rel reo rer res ret rib rie rii rik ril rio rir ris rit rkb rke rkk rko rks rkt rle rli rll rlo rlr rls rlt rob roe roi rok rol roo ror ros rot rrb rri rrk rrl rrr rrs rrt rsb rse rsi rsk rsl rso rsr rss rst rtb rte rti rtk rtl rto rtr rts rtt sbb sbe sbi sbk sbl sbo sbr sbs sbt se- seb see sei sek sel seo ser ses set sib sie sii sik sil sio sir sis sit sk- skb ske ski skk skl sko skr sks skt slb sle sli slk sll slo slr sls slt sob soe soi sok sol soo sor sos sot sr- srb sre sri srk srl sro srr srs srt ss- ssb sse ssi ssk ssl sso ssr sss sst stb ste sti stk stl sto str sts stt tbb tbe tbi tbk tbl tbo tbr tbs tbt te- teb tee tei tek tel teo ter tes tet tib tie tii tik til tio tir tis tit tkb tke tkk tkl tko tkr tks tkt tle tli tlk tll tlo tlr tls tlt to- tob toe toi tok tol too tor tos tot trb tre tri trk trl tro trr trs trt tsb tse tsi tsk tsl tso tsr tss tst ttb tte tti ttk ttl tto ttr tts ttt